I have a wood framed sled bed and the slats under the mattress were bowing and causing the mattress to sag in the middle. I was was actually worried there would be a night that the slats were going to finally break causing the footings to slip which were propped up with pieces of wood so it wasnt sturdy at all. This frame just unfolds and locks into place with a couple screws to place to secure the 2 frames for the king size. It fit perfectly inside the frame and for the first time in a very long time I slept awesome and woke up without a neck and back ache! I definitely recommend this product!   Now we are going to get more time out of our current mattress!